Sealed-beam lamp and method of manufacture



1961 v. 1.. PLAGGE ET AL 3,010,045

SEALED-BEAM LAMP AND METHOD OF MANUFACTURE 2 Sheets-Sheet 1 Filed May 27, 1955 INVENTORJ', [Erma/v 4. Fl/YGGE, AIDE/419A! 0. E5555".

wmavg Nov. 21, 1961 v. PLAGGE ET AL SEALED-BEAM LAMP AND METHOD OF MANUFACTURE 2 Sheets-Sheet 2 Filed May 27, 1955 j l 3 0 M a m 5 m w m 5 ll s M 6 0 H W4 w 4 a H M n W m 3,910,045 SEALED-BEAM LAMP AND METHOD OF, MANUFATURE Vernon L. Plagge, East Orange, and Norman C. Reese,

Verona, N..l., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa, a corporation of Pennsylvania Filed May 27, 1955, Ser. No. 511,516 Claims. (Cl. 313-113) This invention relates to sealed-beam lamps and, more particularly, to sealed-beam lamps wherein the major component parts are sealed together with plastic material, and to a method of making such lamps.

Heretofore sealed-beam lamps have been generally constructed as disclosed in co-pending application of Karl H. Neulinger, Serial No. 504,430, filed April 28, 1955, now abandoned, titled Sealed Beam Automobile Headlight and Shield Therefor and owned by the present assignee. Such lamps as therein disclosed utilize borosilicate or so-called hard glass for the lens and reflector members because the fusion temperature required to fuse the lens to the reflector with localized heating techniques would cause glass failures in so-called soft glass due to its relatively high coeflicient of thermal expansion. The lens and reflector members in a sealed-beam lamp must be relatively heavy to withstand the shoclrs of manufacturing and handling and the requirement of a relatively low coeflicient of expansion which is inherent in the borosilicate type of glass makes possible the local fusion of the hard glass reflector and lens members when fabricating the envelope.

The use of hard glass has several disadvantages, among which is the difficulty of working and preparing the glass and the higher cost of materials, as compared to a soft glass. Also, it is more easy to control pressed soft glass parts, thus allowing for better tolerance in the finished pressed glass members. In addition, the high fusion temperatures required during envelope fabrication necessitates the use of aluminum reflecting surfaces on the concave surface of the reflector member since a silver reflecting surface will discolor or peel off at the relatively high temperatures to which portions of the reflecting surface are subjected during fusion. Since the reflectivity of silver is about fifteen to twenty percent higher than aluminum, it is advantageous to use a silver reflecting surface.

Infrared reflector lamps, which have considerable application for the armed services for night signaling and illumination purposes, require the use of an infrared filter. Since a sealed-beam type of lamp is particularly adapted for such armed services requirements because of its high efficiency and ruggedness, it is highly desirable to form the lens of infrared filter material. Such filter material, however, normally has a relatively high coeflicient of expansion, thereby precluding fabrication of the infrared sealed-beam type of lamps by fusion of the filter member to the reflector member.

It has been suggested in prior art practices to bond soft glass lens and reflector members with a bonding glass which has a softening point lower than the reflector and lens softening points. This has not been practical, however, since the low softening point bonding glass must be heated to around 580 C. or over, to effect a bond between the lens and reflector. Where hard glass lens and reflector members are fused together, as in the general practices of the prior art, a limited area of the reflector and lens is heated to effect such peripheral fusion and with such a limited area of heating the aluminum reflecting coating will not be deleteriously affected. However, soft glass lens and reflector members cannot be heated in such a localized manner to soften the bondif 3,01%45 E Patented Nov. 21, 1961 ing glass, but must be heated in an oven to avoid cracking these members due to the high coefiicient of expansion of the glass. On heating to 500 C., to cause the low temperature softening point glass to bond the soft glass lens and reflector members at their peripheries, the aluminum reflecting coating is deleteriously affected.

It is the general object of the invention to avoid and overcome the foregoing and other difliculties of and objections to prior-art practices by the provision of a sealed-beam lamp and method of making same in which the lens and reflector members may be fabricated of soft glass and are sealed together by means of an organic plastic material.

. It is a further object to provide a sealed-beam lamp wherein the lead-in conductors and exhaust tribulation as well as the lens and reflector members are hermetically sealed into a lamp unit by an organic plastic material.

It is a further object to provide an infrared search or signal lamp wherein the infrared filter can be incorporated as a lens in a sealed-beam type of lamp.

It is still another object to provide a sealed-beam type of lamp in which the lens is sealed to the reflector by means of a plastic material with the reflector having a silver reflecting surface.

The aforesaid objects of the invention, and other objects which will become apparent as the description proceeds, are achieved by providing the lens and reflector members with peripherial surfaces so designed that the sealing resin ingress to the interior of the envelope will be inhibited and a double seal will be formed between the reflector and lens member peripheries. In addition, the lead conductors are provided with bushing means to inhibit ingress of sealing resin into the envelope during envelope fabrication. Further, a method is provided for fabricating such a sealed-beam lamp.

For a better understanding of the invention reference should be had to the accompanying drawings wherein:

FIG. 1 is a sectional elevation of a sealed-beam lamp fabricated in accordance with the teachings of this in- ;ention and utilizing soft glass reflector and lens memers;

FIG. 2 is a fragmentary sectional enlargement of the plastic seal between the lens and reflector members as illustrated in FIG. 1;

FIGS. 3 and 4 are fragmentary enlargements corresponding to FIG. 2 showing two alternative embodiments;

FIG. 5 is a sectional fragmentary enlargement showing the lead conductor seal and exhaust tubulation seal for the embodiment illustrated in FIG. 1;

FIG. 6 is a perspective enlargement of the bushing which is utilized in effecting the lead conductor seal as illustrated in FIG. 5;

FIG. 7 is a sectional elevation similar to FIG. 1 wherern the reflector is fabricated of hard glass and the lens member is fabricated of either soft or hard glass;

FI G. 8 is a fragmentary enlargement of the envelope flushrng step when curing the lens and reflector seal.

Although the principles of the invention are broadly applicable to a sealed-beam type of lamp whereina hermetically sealed envelope encloses a light source, which hght source may either be contained within the single sealed-beam envelope or provided with a separate smaller envelope, the invention is usually employed with a single-envelope type of sealed-beam lamp and hence it has been so illustrated and will be so described.

The terms soft and hard glass are well-known in the art and are indicative of the coeflicient of expansion of the glass. For example, a representative soft glass such as soda-lime glass has a coeflicient of about 92x10 while a representative hard glass such as a borosilicate glass has a coefficient which may vary from 30 to 40X for example.

With specific reference to the form of the invention illustrated in the drawings, the numeral 10 in FIG. 1 indicates generally a sealed-beam lamp having a lens member 12 hermetically sealed at its periphery to the periphery of a concave reflector member 14, which carries a refleeting coating 16 on the inner surface thereof. Preferably the reflector has a parabolic configuration, although other configurations may be utilized for special beam patterns. Lead conductors 18 are hermetically sealed through the back of the reflector 14 and support a filament 20 or other light source, such as a cesium lamp, between their inwardly extending extremities. In the case of a parabolic reflector, the light source is positioned substantially at the focus, as is customary. The portions of the lead conductors 18 which extend without the lens-reflector envelope are adapted to be connected to a source of electrical power (not shown). A sealed exhaust tubulation 22 is also provided at the back of the reflector member 14 and is needed to facilitate lamp fabrication, as will be hereinafter explained.

The thermosetting organic plastic material which has been found suitable for sealing the lens and reflector peripheries and for sealing the lead conductors and exhaust tabulation through the soft glass reflector member, may be generally categorized as an epoxy resin. Epoxy resins are marketed under various trade-marks such as Epon by Shell Chemical Corp., Emeryville, Calif., and Araldite by Ciba Company, Inc., New York, New York. These epoxy resins represent an entirely new class of condensation polymers and a typical formula for these resins is as follows:

A catalyst is required to cause these resins to polymerize and on polymerization the chain lengthens and there is considerable cross-linking between individual chains. Epoxy catalysts, to name a few, are amines such as ethylenediamine, diethylenetriamine, tetraethylenepentamine, piperidine, and metaphenylenediamine. With the foregoing amine catalysts, the amount which is required may vary from about six to fifteen percent by weight of the resin, but once the catalyst is mixed with the epoxy resin the pot life is relatively short. Other types of catalysts are phthalic anhydride which may be used in proportions of about thirty percent by weight of the epoxy, dichloromaleic anhydride and amine borates such as tetraethylene amine borate. For an application such as sealing glass members together on a production basis, it is preferable that the epoxy resin and the catalyst therefor be adapted to be mixed without reacting until heat or some other type of mechanism to trigger the reaction of the epoxy and its catalyst is applied. It has been found that an Araldite AN-IOO epoxy resin which contains about thirty percent phthalic anhydride catalyst is very suitable for such an application for this epoxy resin and its catalyst may be mixed and remain inactive indefinitely until heated to a temperature of about 250 C., at which time the epoxy resin and its catalyst go from a powder phase into a fluid phase before polymerizing and cross-linking to effect resin curing and adhesion of the members being secured. It should be noted that other plastic materials may be developed in the future which will be as suitable for this application as epoxy-type resins, but at this time no other suitable plastic material has been found. However, no matter what type of non-vitreous plastic sealing material is utilized, it should be capable of remaining chemically inactive until the reaction is triggered by heat, for example. Thus it will be appreciated that in fabricating sealed-beam lamps on a production basis, where high volume is required, the epoxy resin and catalyst therefor, or suitable other sealing material, preferably should have an extended pot life until it is desired to effect the seal.

In the preferred embodiment as illustrated in FIGS. 1 and 2, the concave side of the light-transmitting lens member 12 has a periphery 22 which may take the form of a frustoconical surface. This lens periphery 22 is bounded by a circurnscribing lip 24 and the lip and periphery combine to form a depression 26 at their jointure. The reflector member 14 is provided with a reflector periphery 28 which is adapted to fit snugly with the lens periphery 22. The maximum diameter of the reflector periphery 28 is slightly less than the inner diameter of the lens lip 24 so that the lens lip will overlap a small portion of the outer surface of the reflector member.

For the preferred embodiment as illustrated in FIG. 2, the lens periphery 22 preferably has a right-circular frusto-conical configuration wherein the cone base is greater than the cone height with the cone apex positioned behind the plane formed by the cone base, as viewed in front elevation looking into the lens member 12. As a specific example, the frusto--conical shaped lens periphery 22 may have a cone side dimension of one quarter inch, the cone base may have a maximum diameter of 6 inches and the cone height may be 1 inch. The circumscribing lip may extend above the depression 26 formed by the intersection of the periphery 22 and lip 24- a distance of about & inch, for example. The reflector member periphery 28 may have a frusto-conical configuration substantially similar in dimensions and orientation to the lens periphery and a maximum peripheral diameter of 6 inches.

The depression 26 may vary in size as necessitated by the application and in the alternative embodiment of FIG. 3 the depression 26a, as determined by the lens periphery 22a and the lens lip 24a, has considerable length as compared to the preferred embodiment of FIG. 2. Of course the reflector periphery 28a should also be modified to fit snugly with the modified lens periphery 2.2a.

In FIG. 4 is illustrated yet another embodiment wherein the reflector member 1412 is provided with a reflector lip 30, and the reflector periphery 23b and reflector lip 30 form the depression 2612 on the reflector member. The lens member periphery 22b is then adapted to fit snugly into the lens periphery receiving reflector portion which is formed by the reflector member lip 30 and periphery 28b.

In FIG. 5 is illustrated the sealing arrangement for sealing the lead connectors 13 and exhaust tubulation 22 through the back of the reflector 14. This is accomplished by placing the lead conductors 18 through receiving apertures 32 which are provided through the back of the reflector 14. A bushing 34 such as is illustrated in perspective view in FIG. 6 is placed over the lead conductor 18 being sealed and the bushing 34 cooperates with the lead conductor 18 and annular depression 36 in the back of the reflector to limit ingress of epoxy resin into the lamp during the lead-conductor sealing operation and to strengthen the sealed lead conductors against lateral shock.

The circular exhaust tubulation 22 which is preferably of metal such as stainless steel, but which may be of glass, for example, fits into a tapered aperture 38 in the back of the reflector 14 and the outer diameter of the exhaust tubulation cooperates with the bottom portion of the tapered aperture 38 to provide a relatively tight fit to prevent ingress of epoxy resin into the envelope during the sealing operation.

In FIG. 7 is illustrated an alternative embodiment of the invention wherein a hard glass type of reflector 40 is sealed onto a soft or hard glass lens 12. The advantage of this construction is the use of usual type of lead conductor-ferrule arrangement, such as is illustrated in FIG. 1 of the heretofore referred to Neulinger copending application. In' such a construction, the ferrules 42 are sealed into the back of the hard glass reflector by pressing the ferrules into the glass while it is heated to a softened condition. This is impractical where soft glass is utilized since the strains occasioned by heating soft glass to its softening temperature must be relieved by a lengthy annealing process which is impractical from a production standpoint and which limits such a ferrule-lead conductor arrangement to a hard glass reflector member.

In fabricating the preferred embodiment of this invention, the concave surface of the reflector member 14 has applied thereto the aluminum or silver reflecting surface 16, by well-known vacuum metallizing techniques. The reflector member 14 is then placed in a horizontal position with the periphery 28 downward. Lead conductors 13 are then inserted into the apertures 32 provided in the back of the reflector and bushings 34 are placed over each of the lead conductors so that they fit tightly around the lead conductor and against the bottom of the annular bushing receiving depression 36. The projection of the lead conductor into the concave portion of the reflector may be limited by a block (not shown) placed Within the concave portion of the reflector unit. The exhaust tubulation 22 is placed into the exhaust tubulation receiving aperture 38 provided in the back of the reflector. The tubulation fit can be made snug enough so that additional retaining means are not required to hold the tubulation until the resin cures and seals same into the reflector.

In should be pointed out that while phthalic anhydride catalyst is preferred, other epoxy catalysts which effect polymerization upon the application of heat may be utilized. Also, if sealed-beam type of lamps are to be fabricated on a hand, rather than a production basis, epoxy catalysts which effect polymerization immediately upon mixing may be utilized, such as the aforementioned amine examples. It should also be clear that the heretofore given examples of exopy resin catalysts are by no means complete.

With the preferred phthalic anhydride catalyst and an epoxy resin such as marketed by Ciba under the trademark Araldite AN-lOO, several objectionable features arise. For example, the epoxy resin which may be applied in powder form goes through a liquid phase before polymerizing and during polymerization and after same possesses a vapor pressure which will produce a white deposit on the members which are sealed together. In addition, it is highly desirable to prevent as much epoxy resin as possible from getting on the interior portions of the sealed-beam lamp since once this resin has polymerized it is virtually impossible to remove and any foreign substance on the interior of the envelope will deleteriously affect the light output as well as the appearance. These deposits are substantially eliminated by the sealing techniques of this invention.

In sealing the leads 1S and tubulation 22 into the reflector 14, 100 milligrams of Araldite AN-lOO epoxy resin may be used for each lead conductor and tubulation seal. This uncured resin is placed over the bushing and between the exhaust tubulation and its receiving aperture and the lamp reflector unit is baked at about 250 C. for eight minutes. The epoxy resin will be cured by this heating treatment to form an hermetic seal between the lead conductors 18 and exhaust tubulation 22 and reflector member 14. The close fit between the central bushing indentation and the-lead conductor tends to inhibit any ingress of epoxy resin into the concave portions of the reflector member While the epoxy resin in a liquid phase before it is cured. Also, the elongated centrally disposed flare 4-3 on the bushing, when sealed to the lead conductor by means of the epoxy resin, imparts considerable strength to the lead conductor sealing to inhibit any failures of the lead conductor seals under lateral stresses.

The portions of the lead conductors 18 which extend within the concave reflector may then be bent by hand or by machines which are well-known in the art and the light source mounted therebetween either by hand or by well-known machines. Normally this light source will consist of a coiled refractory metal filament such as tungsten, but it may consist of an integral cesium vapor source, or other gas-discharge source such as illustrated in Patent No. 2,562,887 to Beese, one of the co-inventors herein. A cesium vapor lamp is particularly adapted to an infrared illumination or signaling lamp.

A lens member 12, such as illustrated in FIG. 1, is then placed in a horizontal disposition with the periphery upwards and epoxy resin and a catalyst therefor, such as the preferred Araldite AN-lOO epoxy-resin is placed into the depression 26, preferably While the lens member 12 is heated to about C. which causes the epoxy resin to pass into a liquid condition. It has been found that two grams of epoxy resin are suitable for sealing the standard sealed-beam type of lamp which has a peripherial diameter of seven inches. The reflector member 14 with the mounted light source is then placed over the lens member 12 with the reflector periphery 23 fitting against the lens periphery 22 and the lens lip 24 overlapping a portion of the outer surface of the reflector. This forms an unsealed envelope and this unit is placed within an oven in its horizontal disposition and heated to 250 C. for fifteen minutes, for example. On heating, the epoxy resin and catalyst will go through a liquid or semi-liquid phase before curing and while in this phase most of the epoxy resin will be retained within the lowest portions of the depression because of gravity. Flow of the epoxy between the lens and reflector member peripheries into th interior portions of the envelope is inhibited because of the snug fit of these peripheries and the surface tension of the epoxy resin. Some of the resin, however, Will find its way into this peripheral area to form an hermetic seal between these peripheral portions. he epoxy resin will also form a seal between the portion of the outer surface of the reflector which is encased by the lens lip, and the lens lip. A double hermetic seal is thus formed, that is, one seal between the member peripheral portions and one seal between the lip and the reflector. This will increase the strength of the hermetic seal and in addition will insure that a hermetic seal will result.

When sealing the alternative embodiment as is illustrated in FIG. 3, the order is reversed, that is, the reflector unit is placed in substantially horizontal position with peripheral portions upward.

The epoxy resin-catalyst sealing medium will possess a vapor pressure during and after curing. Material deposits resulting from this vapor pressure are not noticeable at the lead conductor and exhaust tubulation seals because of the relatively small amount of resin used to effect the seal and.because the close fit of the bushings and the exhaust tubulation into their respective reflector apertures allow but little ingress of resin into the envelope. When sealing the lens and reflector members, however, a much larger amount of epoxy material is used and even though the ingress of the epoxy resin into the envelope is limited by the snug fit of the respective peripheries, the materials creating the epoxy resin and catalyst vapor pressure will result in a white deposit upon the inner envelope surfaces. To eliminate this white deposit, it has been found that the envelope should be flushed with air or preferably with inert gas such as nitrogen, argon, or other suitable gas. It is preferred to use nitrogen because it is relatively inexpensive. This inert gas flushing is accomplished by a flushing tube 44 which fits inside the exhaust tubulation 22 and nitrogen gas, for example, is pumped in through the inner tube 44- and is expelled through the exhaust tubulation 22. When sealing a seven-inch sealed-beam lamp, it has been found that 500 cubic centimeters per minute of flushing nitrogen gas is suitable to carry away the volatile resin material. In addition this flush tends to remove substantially all moisture from the lamp. This flushing procedure need only be carried out while the resin is being cured.

After the envelope has been fabricated by sealing the ens 12 to the reflector t4, the lamp is exhausted through the exhaust tubulation 22 by well-known procedures. In the case of a filamentary sealed-beam type of lamp, as illustrated in FIG. 1, the envelope is then provided with a filling of a mixture of ninety percent argon and ten percent nitrogen at a pressure of 600 mm., for example. The exhaust tube is then sealed by well-known pressure tip-off procedures.

It will be recognized that the objects of the invention have been achieved by providing a sea-ledbeam lamp and method in which the lens and reflector members may be fabricated of soft glass and are sealed together by means of a thermosetting plastic material. In addition, the lead conductors and exhaust tribulation may also be hermetically sealed into the lamp by means of such plastic material and if desired the lamp can readily be converted to an infrared search or signal lamp by iu= corporating a soft glass infrared filter. Also, the lamp may be provided with a silver reflecting surface, if desired, to increase the light output.

While in accordance with the Patent Statutes one best known embodiment of the invention has been illustrated and described in detail, it is to be particularly understood that the invention is not limited thereto or thereby.

We claim:

1. A sealed-beam headlamp comprising a vitreous refleeting member having a concave surface terminating in a reflector peripheral surface and having a reflecting coating carried on said concave surface, a light-transmitting lens member terminating in a lens peripheral surface, at least one of said members being fabricated of soft glass, said lens peripheral surface and said reflector peripheral surface being hermetically sealed together with a thermosetting plastic material to form an envelope, the peripheral surface of one of said members being bounded by a circumscribing lip, a depression formed by said lip and said one member peripheral surface, said depression having sides defined by said lip and said one member peripheral surface, said depression being so disposed that when said one member is maintained in a horizontal disposition with said peripheral surface upward said depression sides will be higher than the lowermost portion of said depression, the other member having an outer surface and a peripheral surface which cooperates with said one member peripheral surface to form a snug fit, said lip encasing a portion of said outer surface of said other member which is adjacent said other member peripheral surface, said lip and said other member lip encased outer surface being hermetically sealed together with thermosetting plastic material, a sealed exhaust member and a plurality of lead conductors hermetically sealed through the back of said reflector member, and a light source positioned between said lead conductors and Within said envelope in definite optical relationship to said reflecting surface.

2. A sealed beam lamp comprising a vitreous reflecting member having a concave surface terminating in a reflector peripheral surface and having a reflecting coating carried on said concave surface, a light-transmitting lens member terminating in a lens peripheral surface, said lens peripheral surface and said reflector peripheral surface being hermetically sealed together with an epoxy resin to form an envelope, the peripheral surface of one of said members being bounded by a circumscribing lip. a depression formed by said lip and said one member peripheral surface, said depression having sides defined by said lip and said one member peripheral surface, said depression being so disposed that when said one member is maintained in a horizontal disposition with said peripheral surface upward said depression sides will be higher than the lowermost portion of said depression, the other member having an outer surface and a peripheral surface which cooperates with said one member peripheral surface to form a snug fit, said lip encasing a portion of said outer surface of said other member which is adjacent said other member peripheral surface, said lip and said other member lip encased outer surface being hermetically sealed together with epoxy resin, a sealed exhaust member and a plurality of lead conductors hermetically sealed through the back of said reflector member, and a light source positioned between said lead conductors and within said envelope in definite optical relationship to said reflecting surface.

3. A sealed-beam lamp comprising a vitreous reflecting member having a concave surface terminating in a reflector peripheral surface and having a reflecting coating carried on said concave surface, a light-transmitting lens member terminating in a lens peripheral surface, at least one of said members being fabricated of soft glass, said lens peripheral surface and said reflector peripheral surface being hermetically sealed together with an epoxy resin to form an envelope, the peripheral surface of one of said members being bounded by a circumscribing lip, a depression formed by said lip and said one member peripheral surface, said depression having sides defined by said lip and said one member peripheral surface, said depression being so disposed that when said one member is maintained in a horizontal disposition with said peripheral surface upward said depression sides will be higher than the lowermost portion of said depression, the other member having an outer surface and a peripheral surface which cooperates with said one member peripher- 211 surface to form a snug fit, said lip encasing a portion of said outer surface of said other member which is adjacent said other member peripheral surface, said lip and said other member lip encased outer surface being hermetically sealed together with epoxy resin, a sealed exhaust member and a plurality of lead conductors hermetically sealed through the back of said reflector member by means of epoxy resin, bushing means provided between said lead conductors and said vitreous reflector member to limit clearance, and a light source positioned between said lead conductors and within said envelope in definite optical relationship to said reflecting surface.

4. A sealed-beam lamp comprising a vitreous reflecting member having a concave surface terminating in a reflector peripheral surface and having a reflecting coating carried on said concave urface, a light-transmitting lens member terminating in a lens peripheral surface, at least one of said members being fabricated of soft glass, said lens peripheral surface and said reflector peripheral surface being hermetically sealed together with an epoxy resin to form an envelope, the peripheral surface of said lens member being bounded by a circumscribing lip, a depression formed by said lip and said lens member peripheral surface, said depression having sides defined by said lip and said lens member peripheral surface, said depression being so disposed that when saidlens member is maintained in a horizontal disposition with said peripheral surface upward said depression sides will be higher than the lowermost portion of said depression, said reflector member having an outer surface and a peripheral surface which co-perates with said lens member peripheral surface to form a snug fit, said lip encasing a portion of said outer surface of said reflector member which is adjacent said reflector member peripheral surface, said lip and said reflector member lip encased outer surface being hermetically sealed together with epoxy resin, a sealed exhaust member and a plurality of lead conductors hermetically sealed through the back of said reflector member by means of epoxy resin, bushing means provided between said lead conductors and said vitreous reflector member to limit clearance, and alight source positioned between said lead conductors and within said envelope in definite optical relationship to said reflecting surface.

5. A sealed-beam lamp comprising a vitreous reflecting member having a concave surface terminating in a reflector peripheral surface and having a reflecting coating carried on said concave surface, a light-transmitting lens member terminating in a lens peripheral surface, at least one of said members being fabricated of soft glass, said lens peripheral surface and said reflector peripheral surface being hermetically sealed together with an epoxy resin to form an envelope, the peripheral surface of said lens member being bounded by a circumscribing lip, a depression formed by said lip and said reflector member peripheral surface, said depression having sides defined by said lip and said reflector member peripheral surface, said depression being so disposed that when said reflector member is maintained in a horizontal disposition with said peripheral surface upward said depression sides will be higher than the lowermost portion of said depression, said lens member having an outer surface and a peripheral surface which cooperates with said reflector member peripheral surface to form a snug fit, said lip encasing a portion of said outer surface of said lens member which is adjacent said lens member peripheral surface, said lip and said lens member lip encased outer surface being hermetically sealed together with epoxy resin, a sealed exhaust member and a plurality of lead conductors hermetically sealed through the back of said reflector member by means of epoxy resin, bushing means provided between said lead conductors and said vitreous reflector member to limit clearance, and a light source positioned between said lead conductors and within said envelope in definite optical relationship to said reflecting surface.

6. The method of fabricating a light-transmitting lens member and a reflector member having lead conductors and an exhaust tubulation sealed therethrough and a light source mounted between said lead conductors in definite optical relationship to said reflector member into a sealedbeam lamp, comprising placing the peripheral surface of said light-transmitting lens member over the peripheral surface of said reflector member to form an unsealed envelope, one of said reflector and lens member peripheral surfaces being bounded by a circumscribing lip, a depression formed by said lip and said one member peripheral surface and including an uncured epoxy resin and an epoxy resin catalyst in said depression, placing said depression in a substantially horizontal and up- Ward orientation, heating said reflector and said lens to cure said depression-held epoxy resin to form an hermetic seal between said reflector and said lens peripheral surfaces and between said lip and said other member, flushing with inert gas through said exhaust tubulation while heating said envelope, exhausting said envelope, and filling with inert gas and sealing off said exhaust tubulation.

7. The method of fabricating a sealed-beam lamp comprising, positioning lead conductors and an exhaust tubulation through apertures in the back of a concave reflector member having a periphery, providing bushings between said lead conductors and said apertures, placing uncured epoxy resin and an epoxy resin catalyst between said reflector member and said lead conductors, said bushings and said exhaust tubulation, heating said reflector to cure said epoxy resin to form hermetic seals, mounting a light source between said lead conductors in definite optical relationship to said reflecting surface, placing the periphery of a light-transmitting lens member over said reflector periphery to form an unsealed envelope, one of said reflector and lens member peripheries being bounded by a circumscribing lip, a depression formed by said lip and said one member periphery and including an uncured epoxy resin and an epoxy resin catalyst therein, placing said depression-possessing periphery in a substantially horizontal and upward orientation, heating said reflector and said lens to cure said depression-held epoxy resin to form an hermetic seal between 10 said reflector and said lens peripheries and between said lip and said other member, flushing with inert gas through said exhaust tubulation while heating said envelope, exhausting said envelope, and filling said envelope with inert gas and sealing oif said exhaust tubulation.

8. A method of hermetically sealing the peripheral surface of a light-transmitting lens member to the peripheral surface of a reflector member to form an envelope, one of said members having a lip about its peripheral surface to form a liquid-containable depression, said reflector member having an exhaust tubulation sealed therethrough: comprising placing uncured epoxy resin and a heat-actuated catalyst therefor in said depression, placing said member peripheral surfaces together with said depression in a substantially horizontal liquid-containing position, applying heat to said members to cure said epoxy resin and simultaneously flushing with inert gas through said exhaust tubulation, exhausting said envelope, and filling said envelope with inert gas and sealing off said exhaust tubulation.

9. A method of hermetically joining the peripheral surface of a light-transmitting lens member to the peripheral surface of a member carrying a reflecting coating on its interior surface, one of said members having a lip about its peripheral surface to form a liquid-containable depression, said lens and reflector members having 00- eflicients of expansion which are substantially different, said reflector member having an exhaust tubulation sealed therethrough: comprising placing uncured epoxy resin and a heat-actuated catalyst therefor in said depression, placing said member peripheral surfaces together with said depression in a liquid-containing position, applying heat to said members to cure said epoxy resin and simultaneously flushing with inert gas through said exhaust tubulation, exhausting said envelope, and filling said envelope with inert gas and sealing off said exhaust tubulation.

10. A method of hermetically joining the peripheral surface of a light-transmitting vitreous lens member to the peripheral surface of a vitreous member carrying a reflecting coating on its interior surface, one of said members having a lip about its peripheral surface to form a liquid-containable depression, said lens and reflector members having coefiicients of expansion which are substantially different, said reflector member having an exhaust tubulation sealed therethrough: comprising placing uncured epoxy resin and a heat-actuated catalyst therefor in said depression, placing said member peripheral surfaces together with said depression in a liquidcontaining position, applying heat to said members to cure said epoxy resin and simultaneously flushing with inert gas through said exhaust tubulation, exhausting said envelope, and filling said envelope with inert gas and sealing off said exhaust tubulation.

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